JP2008049147A - Ball - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ball to be appropriately used mainly for volleyball or beach volleyball, excellent in the controllability in the play in total including tossing and serving, having an original three-dimensional outside appearance with excellent design and a sufficient surface frictional strength. <P>SOLUTION: The ball is made of a sheet-like object. An elastomer coating layer is layered on the surface of a fiber base material, and continuous projections and discontinuous recesses are formed on the surface of the coating layer. The discontinuous recesses are formed at average intervals of 0.5-3 mm. The depth of the recess is 50-500 μm, and the vertically projected area of each recess is 1-5 mm<SP>2</SP>. The ratio of the total vertically projected area of the recesses to the surface area of the coating layer is 3-30%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a volleyball ball or a beach volleyball ball. More specifically, the present invention is suitable for use in volleyball and beach volleyball, which has sufficient surface wear strength and excellent cushioning properties, and has controllability when tossing the ball while having an excellent appearance with a three-dimensional effect. It relates to a ball that can

Various characteristics are required for volleyball and beach volleyball. For example, a surface material that repeats friction and collision with the ground or floor surface is required to have a high level of surface wear strength. Soft cushioning that reduces the impact on the fingertips and arms and controllability are required. More recently, good controllability is often required even when the ball surface gets wet with sweat.
Conventionally, various methods have been proposed as a method for obtaining a ball having a high level of surface wear strength and cushioning properties and a leather-like appearance and texture as palatability.
For example, a nonporous polymer elastic body layer (first layer), a porous polymer elastic body layer (second layer), a layer composed of a polymer elastic body and a nonwoven fabric (third layer), and a nonwoven fabric layer (first layer) A leather-like sheet composed of at least four layers (four layers) and a ball composed of the leather-like sheet have been proposed (Patent Document 1).
reference). However, in the method of Patent Document 1, when the first layer and the second layer are formed using a polymer elastic body having durability that can withstand actual use, the cushioning property is insufficient, the controllability of the ball, the flight It was not satisfactory in terms of performance.

In addition to cushioning properties, a transparent non-porous layer mainly composed of polyurethane on the surface of a fibrous base material having a concavo-convex pattern coated with a polyurethane layer as a leather-like sheet having an excellent appearance in three dimensions Is a synthetic leather in which an air layer exists between the concave portion and the nonporous layer, and the total area of the bonding portion of the convex portion and the nonporous layer is the surface area of the synthetic leather. Synthetic leather that is 50 to 90% of the above has been proposed (see Patent Document 2). However, in Patent Document 2, as in the case of volleyball and beach volleyball, a ball that is handled by hand does not have both cushioning properties and durability that can withstand practical use. We were not satisfied with point.
Moreover, it has a convex part substantially continuous on the surface and a concave part adjacent thereto, the height difference between the convex part and the concave part is 50 to 1000 μm, the vertical projection area of the adjacent concave part is 3 to 30 mm ² , A ball having an average interval of 0.5 to 3 mm and a total area of vertical projection areas of the recesses of 30 to 60% of the total area of the sheet has been proposed (see Patent Document 3). However, this ball is suitable for a ball that is grabbed with a hand such as basketball, but a ball that is hit with a hand like volleyball is in terms of impact when hit, controllability of the ball, and flight performance. It was not satisfactory.
Furthermore, by forming a secondary concavo-convex part on the upper surface of the primary bulge part, basketball that can exhibit excellent non-slip properties even when wet is proposed by meshing with the fine concavo-convex part of the hand gripping the ball. (See Patent Document 4). However, this ball is also suitable for a ball that is grabbed with a hand such as basketball. However, in a ball that is hit with a hand like volleyball, in terms of impact when hit, controllability of the ball, and flight performance. It was not satisfactory.
JP 2000-102629 A JP-A-11-93081 International Publication WO2005 / 97268 JP 2005-87315 A

  Under such circumstances, the present invention has a surface wear strength sufficient as a surface material of a ball for ball games and a soft cushioning property while having an excellent appearance with a three-dimensional effect, and has controllability and flight performance. An object is to provide a ball that can be suitably used for excellent volleyball and beach volleyball.

As a result of intensive studies to achieve the above-mentioned object, the present inventors have provided a substantially continuous convex portion by discontinuously providing concave portions at short intervals on the surface of the sheet-like material forming the ball. The inventors have found that the above-mentioned problems can be solved by the assignment, and have completed the present invention.
That is, in the present invention, as shown in FIG. 1, the polymer elastic body coating layer 1 is laminated on the surface of the fiber base 2, and the convex portions 4 and the discontinuous concave portions 3 are formed on the surface of the coating layer 1. The discontinuous recesses 3 are formed with an average interval of 0.5 to 3 mm, the recesses 3 are 50 to 500 μm deep, the vertical projection areas of the individual recesses 3 are 1 to 5 mm ² , and the individual recesses with respect to the surface area of the coating layer A ball for volleyball or beach volleyball is provided, which is made of a sheet-like material characterized in that the ratio of the sum of the vertical projection areas of 3 is 3 to 30%.

The ball | bowl of this invention has a substantially continuous convex part by providing a recessed part discontinuously with a short space | interval on the surface of the sheet-like material which forms a ball. Therefore, due to sufficient surface wear strength and excellent cushioning properties of the substantially continuous convex portion, it is possible to reduce the impact on the fingertip and arm when hitting the ball. The concave portion not only provides stable flight performance, but also improves the controllability of the ball by increasing the contact area and contact time between the fingertip and the ball surface. Furthermore, it also has an excellent non-slip property that is difficult to slip even when wet with sweat or water.
That is, the ball of the present invention is excellent in controllability in the whole play from toss to attack to serve.

The sheet-like material forming the ball of the present invention is a sheet-like material comprising a fiber base material and a polymer elastic body coating layer, and a large number of continuous convex portions and discontinuous concave portions formed on the surface of the coating layer. . Here, the “discontinuous recesses” are, for example, a large number of independent concave shapes (recesses) formed by pressing a large number of independent convex shapes arranged at intervals on a flat sheet surface. Say.
As a method for forming the “discontinuous recesses”, any conventionally known method can be adopted as long as a desired recess shape can be stably provided. For example, a method of embossing at least a surface of a sheet-like material having a surface layer formed of a polymer elastic body with an embossing roll having a desired convex shape, or a polymer on a release paper having a desired convex shape A method of using a polymer elastic body coating layer formed by casting and solidifying an elastic body fluid as a surface layer of a sheet-like material can be employed.

Further, each recess is vertically projected area thereof is 1 to 5 mm ^2, the average spacing of the recesses with adjacent 0.5 to 3 mm, and the depth of the recess is required to be 50 to 500 [mu] m. As a method for forming such a discontinuous recess in the numerical range, the method of using the release paper in the above, in the production of the release paper, there is a limit to the depth of the recess of the sheet-like material obtained, When a resin solution is applied to a release paper having a discontinuous convex part, the deeper the convex part (the concave part in the sheet-like material), the easier it is to generate bubbles around it. This is a suitable method when the depth is less than 150 μm. On the other hand, the method of embossing with an embossing roll or the like may use an embossing roll having a convex portion corresponding to the intended depth of the concave portion, and its suitability does not depend much on the desired depth. Therefore, when industrial productivity is taken into consideration, a method of forming with an embossing roll or the like is a preferable method rather than a method of using a release paper.
When forming a desired recessed part using an embossing roll, it can carry out by setting suitably the convex part height of the roll to be used, and the temperature, pressure, and time conditions of the roll. These conditions are
Although not particularly limited, the height of the convex portion of the roll is 80 to 700 μm, and the roll temperature is 150 to 180.
It can adjust in the range of 10 degreeC, pressurization pressure 5-50 kg / cm, and time 10 to 120 second, and can obtain a desired recessed part depth.

  The ball according to the present invention, that is, a ball game ball such as volleyball or beach volleyball, is generally made by stitching a plurality of pieces made of natural leather or synthetic leather, or the core of the ball. It is manufactured by pasting pieces together. Here, the portion where the outer peripheries of the individual pieces are in contact with each other is a streak or a stitch, but the convex part and the concave part on the surface of the sheet-like material referred to in the present invention are not a streak or a stitch formed on the outer periphery of the piece, It refers to the shape formed on the piece surface, and does not include a gas filling port that is generally present on the surface of a gas-filled ball or a logo mark that is locally formed on the ball surface.

The surface shape of a ball used in ball games such as volleyball needs to be in a state where at least one concave portion touches the fingertip when the player randomly holds the ball. Accordingly, as the shape of the ball surface, the depth of the concave portion is 50 to 500 μm, preferably 200 to 350 μm. If the depth of the recess is less than 50μm, it will be slippery when it gets wet with sweat or water, so it will not be effective in controllability especially when tossing, and suppresses orbital shake during flight such as serve It is difficult to obtain the effect. Furthermore, from the viewpoint of merchantability, the design effect is also reduced. On the other hand, when the depth of the concave portion exceeds 350 μm, the non-slip property when wet with sweat or water becomes better and the controllability when raising the toss tends to be improved, but depending on the player, the ball on the fingertip If the depth of the recess exceeds 500 μm, the majority of players will be worried about the point of being caught rather than improving the control of the toss. As a result, the tendency for the evaluation of the controllability of the ball to become worse becomes remarkable.
In addition, as shown in FIG. 3, the “depth of the concave portion” in the present invention means that the distance (D) from the surface of the convex portion to the deepest portion of the concave portion in the coating layer is a cross-sectional photograph in the thickness direction. The average value of 10 measured values.

The vertical projection area of the concave portion in the sheet-like material used in the present invention needs to be 1 to 5 mm ² , preferably 2 to 3 mm ² . When the vertical projection area exceeds 5 mm ² and the individual recesses become large, there is a tendency that a large number of players evaluate that the ball is caught on the fingertips too much when raising the toss. The tendency for evaluation to become worse is remarkable. Furthermore, even the harmful effect that the wearability of the ball is reduced becomes apparent. When the vertical projection area is less than 1 mm ² , there is almost no catching on the finger, and even when it gets wet with sweat or water, it is easy to slip, so there is almost no improvement effect in controllability when tossing. In addition, it becomes difficult to obtain the effect of suppressing orbital shake during flight such as serve. Furthermore, from the viewpoint of merchantability, the design effect is also reduced. In the cross section passing through the deepest part of the concave portion of the sheet-like material, when the concave surface and the surface of the convex portion adjacent thereto are connected by a continuous curve, the angle formed by the perpendicular of the flat portion and the tangent of the concave surface is 45 °. The portion is defined as a boundary (B) between the concave portion and the flat portion (see FIG. 4). On the other hand, if the surface shape is broken, that point is defined as the boundary (B) between the concave portion and the flat portion (see FIG. 5). The projected area in the vertical direction with respect to the surface of the coating layer in the recessed area surrounded by the boundary is referred to as “vertical projected area of the recessed portion”.

  The sum total of the vertical projected areas of the individual recesses is required to be 3 to 30%, more preferably 10 to 25%, as a percentage of the total surface area of the coating layer. When the ratio of the sum of the vertical projection areas of the individual recesses is less than 3%, there is almost no improvement effect in the controllability when tossing, and the effect of suppressing trajectory fluctuations during flight such as serve is also obtained. It becomes difficult. Furthermore, from the viewpoint of merchantability, the design effect is also reduced. On the other hand, if it exceeds 30%, a player who evaluates that the ball is caught too hard on the fingertip when raising the toss even though good evaluation is obtained only from the point of non-slip property when wet with sweat or water Tend to occupy a large number, and the tendency to deteriorate the evaluation of the controllability of the ball as a play total is remarkable. Further, the cross-sectional shape in the thickness direction of the concave portion is preferably an arc shape, a semicircular shape or a trapezoidal shape, and the three-dimensional shape is preferably a hemispherical shape, a truncated cone shape or a truncated pyramid shape. Here, “hemisphere” does not mean a complete hemisphere, but means that the approximate shape is a hemisphere. In addition, “trapezoidal shape” does not mean that it is a perfect trapezoid, but it means that the approximate shape is trapezoidal, for example, the base is not a straight line but is slightly convex. It may be anything. Similarly, an arcuate shape, a semicircular shape, a truncated cone shape, or a truncated pyramid shape may be used as long as they are roughly in such a shape. By making the shape of the recess hemispherical, truncated cone or truncated pyramid, not only can you get a very delicate catch on the fingertip when tossing, but also total control including serve and other play Sex will be obtained in a well-balanced manner.

Moreover, the average space | interval of hemispherical recessed parts in the sheet-like material used by this invention needs to be 0.5-3 mm. When the thickness is less than 0.5 mm, the concave portions are too close to each other, and the shape of the convex portions is partially sharpened, resulting in inferior softness, cushioning properties and touch feeling, and surface wear strength. Moreover, when exceeding 3 mm, it becomes inferior to fit property and non-slip property. The average interval between the recesses is preferably 1 to 2 mm.
The “average interval between recesses” means an average value obtained by photographing the surface with an electron microscope, selecting 10 arbitrary recesses, and measuring the shortest distance between adjacent recesses based on the outer periphery of the recesses. Further, if the concave portions are all curved as described above, a portion where the angle formed by the perpendicular to the sheet surface is 45 ° is a boundary between the concave portion and the convex portion, or if there is a corner, that portion is a boundary between the concave portion and the convex portion. As such, a portion surrounded by the boundary line is defined as the outer periphery.

Further, in the sheet-like material forming the ball of the present invention, it is preferable that the surface of the coating layer has a depth that is less than the depth of the concave portion (primary concave portion) and a secondary irregularity of 10 to 100 μm. . The shape of the secondary irregularities is not particularly limited, but in order to uniformly obtain non-slip properties in all directions, they are arranged on a straight line or a curve in two or more directions such as a lattice, a concentric circle, and a radial shape (see FIG. 6). It may be a shape, a non-uniform shape composed of a plurality of straight lines or curves, a discontinuous recess shape similar to the primary recess, or a combination thereof.
And it is preferable to make the discontinuous recessed part shape similar to the said primary recessed part into the shape of a secondary recessed part at the point which is excellent in the grip property and design property when wet with sweat.
The depth of the secondary recess is preferably in the range of 10 to 100 μm and less than the depth of the primary recess, and more preferably 20 to 70 μm. By making the depth of the secondary recess 10 μm or more, the fingertip and the ball are sufficiently caught, and the toss control is excellent. By setting the depth of the secondary recess to 100 μm or less, the wear resistance and the surface feel are excellent. Furthermore, by making the depth less than the depth of the concave portion, it is possible to have excellent wear resistance and surface tactile feel and to suppress adhesion of dirt.
In addition, the secondary irregularities are formed on the surface of the coating layer other than the primary recesses, particularly on the primary projections, to improve the surface tactile sensation, toss controllability and the straight running stability of the ball during serving. It is preferable at the point of providing dirtiness. Furthermore, when the secondary unevenness is formed on a portion other than the concave portion, it may be formed on the side surface and the upper surface of the convex portion, but in the present invention, it is formed on the upper surface of the convex portion as shown in FIG. It is preferable.
The secondary recess is discontinuous, the vertical projection area is 0.01 to ¹ mm ² , and the ratio of the sum of the vertical projection areas of the individual secondary recesses to the coating layer surface area is 1 to 30%. It is preferable that it is a concave part.
The secondary recess preferably has a vertical projection area of 0.01 to ¹ mm ² in terms of smooth surface tactile sensation, and the ratio of the sum of the vertical projection areas of the secondary recess is 1 to 30%. Consisting of a concave portion makes the ball and the fingertip sufficiently easy to engage with each other, thereby having a more excellent non-slip property. Moreover, it is preferable from the viewpoint that the straightness of the ball is more excellent, and the trajectory is less likely to be shaken especially in a serve where the flight distance of the ball is long, and it is preferably 3 to 20%.

As a method of further forming secondary irregularities on the surface of the coating layer in which discontinuous concave portions are formed in the sheet-like material used in the present invention, the concave portions and the secondary are formed using a release paper capable of forming the concave portions and the secondary irregularities. There is a method of forming unevenness at the same time, a method of embossing secondary unevenness by embossing, etc., but considering industrial productivity, a method of forming by embossing is preferable to a method using release paper. Is the method.
When using the embossing roll to form the desired secondary irregularities, the height of the convex portion of the embossing roll to be used and the conditions of the temperature, pressure and time of the embossing roll can be appropriately set. These conditions are not particularly limited, but the embossing roll height is 80 to 700 μm, the roll temperature is 150 to 180 ° C., the pressing pressure is 5 to 50 kg / cm, and the time is 10 to 120 seconds. Next unevenness can be formed.
It is economical to prepare and use an embossing roll in a shape that can form discontinuous recesses and secondary irregularities in advance so that discontinuous recesses and secondary irregularities can be formed simultaneously by a single embossing process. This is the preferred method.

  In addition, the coloring process can be performed before or after the process of forming the recesses and / or secondary irregularities. For example, in the case of a method of forming with an embossing roll, either before or after the embossing process is possible. However, since the embossing treatment is often performed with heating and may be accompanied by discoloration, it is preferable to perform a coloring treatment for preventing discoloration due to heating before embossing. As the colorant, a pigment is the best from the viewpoint of heat resistance, light resistance, and friction fastness. As a method for treating the colorant, there are a gravure method, a dyeing method, a reverse coating method, a direct coating method, and the like, but the gravure method is optimal in consideration of productivity and cost.

  The thickness of the polymer elastic material coating layer used in the present invention can be arbitrarily selected according to the required physical properties or the texture preferred by the player, and is not particularly limited. 1 to 0.3 mm. If the thickness of the polymer elastic body coating layer is 0.1 mm or more, the minimum required mechanical properties such as wear resistance can be ensured. On the other hand, if the thickness of the polymer elastic coating layer is 0.3 mm or less, the weight of the ball is not affected.

In the present invention, the touch on the surface can be changed as necessary, and water repellency, antifouling properties and the like can be imparted. For example, there are a method of applying a touch modifier resin to at least a part of a discontinuous concave portion or a flat portion, a method of applying a chemical mainly composed of a fluorine-based resin, and the like. Examples of the touch modifier resin include those mainly composed of polyurethane resins, those modified with polyurethane resins, those mainly composed of amino acid resins, and those using powders such as collagen and silk. It can be used according to the purpose.
Various methods can be used as a method for coating the flat portion of the surface of the sheet-like material with such a resin or drug, but it is selectively applied particularly when only the flat portion is coated with a non-slip resin. Is preferably used. As a specific method, there is a method of transferring using a gravure roll. Further, as a method of covering not only the flat portion but also the concave portion, a method of coating the entire surface is used. Specific methods include coating by spraying, coating the entire surface of the surface with a knife coating method, etc., coating the entire surface of the substrate with a resin such as process paper, and forming the substrate via the adhesive layer. There are a method of adhering to a layer, a method of uniformly extruding from a extruder through a die onto a substrate layer, and forming a film on the surface.

  As the fiber base material that can be used for the sheet-like material forming the ball of the present invention, various fiber base materials such as natural leather, leather-like sheet, knitted fabric, and non-woven fabric can be used. When knitted fabric or nonwoven fabric is used as a fiber base material, those containing a high molecular weight polymer can be used if necessary, and any conventionally known leather-like sheet can be used. Is possible. Among these, a leather-like fiber base material composed of a fiber entangled body and a polymer is preferable, and in particular, a polymer is impregnated in a sponge state inside a three-dimensional entangled nonwoven fabric used as a fiber entangled body. Are preferred. This is because the convex portions that are substantially continuous due to the concave portions present on the surface of the sheet-like material mesh with the fingertips that grab the ball, and the touch and texture of the surface of the seat are flexible and have a certain degree of cushioning properties. This is because the non-slip property is improved.

  As a fiber constituting a knitted fabric or a non-woven fabric as a fiber base material, any one of conventionally known natural fibers, synthetic fibers and semi-synthetic fibers can be used as long as the mechanical properties required as a surface material of the ball can be satisfied. Can also be used. Industrially known cellulose fibers, acrylic fibers, polyester fibers, polyamide fibers, and the like are preferably used from the standpoints of quality stability and price. In the present invention, although not particularly limited, an ultrafine fiber capable of realizing a soft texture closer to that of natural leather is preferable, and an average fineness is 0.3 dtex or less, particularly 0.1 dtex or less, and 0.0001 dtex. Ultrafine fibers having the above average fineness are preferably used.

As a method for obtaining such an ultrafine fiber, (a) a method of directly spinning an ultrafine fiber having a target average fineness, and (b) a fine fiber-generating fiber that is once thicker than the target fineness is spun, and then the target And a method of transforming into ultrafine fibers having an average fineness of
As the method (b) for obtaining ultrafine fibers via the ultrafine fiber-generating fibers, two or more thermoplastic polymers having no compatibility are composite-spun or mixed-spun, and at least one of the polymers is produced from the fibers. In general, a method of extracting or decomposing components, or separating and peeling a polymer at an interface between constituent polymers is generally used. As typical fiber forms of the ultrafine fiber generating fiber of the type from which at least one component is removed, a so-called “sea-island fiber”, “multilayer laminated fiber” and the like can be mentioned.
In the case of sea-island fibers, the sea component polymer is extracted or removed by decomposition, and in the case of multilayer laminated fibers, at least one of the laminated component polymers is extracted and removed or decomposed to remove remaining island components. An ultrafine fiber bundle consisting of In addition, as a typical fiber form of the ultrafine fiber generation type fiber that is separated at the interface of the constituent polymer, a so-called petal-like laminated fiber, a multilayer laminated fiber, etc. can be mentioned, and physical treatment or chemical treatment Thus, an ultrafine fiber bundle can be obtained by peeling each other at the interface between different polymers to be laminated.

The island component polymer of the sea-island fiber or multi-layer laminated fiber is a polymer that can be melt-spun and sufficiently exhibits fiber properties such as strength, and has a higher melt viscosity than the sea-component polymer under the spinning conditions, and has a surface Polymers with high tension are preferred. Examples of such island component polymers include polyamide-based polymers such as nylon-6, nylon-66, nylon-610, nylon-612, and copolymers based on these, or polyethylene terephthalate, polypropylene terephthalate, Polyester polymers such as methylene terephthalate and polybutylene terephthalate, and copolymers mainly composed thereof are preferably used.
The sea component polymer of the sea-island fiber or multilayer laminated fiber has a lower melt viscosity than the island component polymer, has different solubility and decomposability with the island component, and is used for dissolving and removing the sea component. Alternatively, a polymer having high solubility in a decomposing agent or the like and low compatibility with the island component is preferable. For example, polyethylene, modified polyethylene, polypropylene, polystyrene, modified polystyrene, modified polyester and the like are preferably used.

  The preferred sea-island volume ratio of the ultra-fine fiber-generating fiber, that is, the sea-island type fiber that suitably generates ultra-fine fibers having a fineness of 0.3 dtex or less is in the range of sea / island = 30/70 to 70/30, preferably 40 / 60 to 60/40. If the sea component is 30% or more, the component that dissolves or decomposes and removes with a solvent or a decomposing agent is sufficient, so that the flexibility of the resulting leather-like sheet can be fully expressed. Therefore, measures such as excessive use of treatment agents such as softeners are not required. Use of an excessive amount of the treatment agent is not preferable because it causes problems such as deterioration in mechanical properties such as tear strength, influence on other treatment agents, influence on touch, and deterioration in durability. Further, if the sea component is 70% or less, the absolute amount of fibers made up of the island component after dissolution or decomposition is sufficient, so that the obtained leather-like sheet is a machine with a sufficient level as a base material for ball materials. The physical properties can be secured stably. In addition, since there are not too many components to dissolve or decompose and remove, there are no problems such as quality irregularities due to defective removal and processing of removed components generated in large quantities, and productivity viewpoints such as production speed and cost. It is also suitable from the industrial viewpoint.

Moreover, the method for producing a three-dimensional entangled nonwoven fabric preferably used as a fiber entangled body is not particularly limited as long as it is a method capable of obtaining a weight and a density suitable for a base material for a ball, and is conventionally known. It can be manufactured by various methods. The fiber used may be a nonwoven fabric made of short fibers or a nonwoven fabric made of long fibers. As a web forming method, any conventionally known method such as a card method, a papermaking method, or a spunbond method can be used. As a web entanglement method, various conventionally known methods such as a needle punch method and a spun lace method can be used alone or in combination.
Among the above-mentioned methods, a particularly preferable method is that a fiber obtained by spinning is stretched to about 1.5 to 5 times, and then mechanical crimps are imparted and cut to a length of about 3 to 7 cm. After that, it is defibrated with a card to form a web of a desired density through a webber, the resulting web is laminated to a desired weight, and then a needle with one or more barbs is used. In this method, the fibers are entangled in the thickness direction by needle punching at about 300 to 4000 punches / cm ² .

Next, the obtained fiber entangled body such as a three-dimensional entangled nonwoven fabric is impregnated with a polymer as necessary. As a method of impregnation, a polymer polymer solution or dispersion is used alone or in a fiber entanglement by a known method such as a dip nip method, a knife coating method, a bar coating method, a roll coating method, or a spray coating method. The polymer is solidified so as to form a large number of voids in a sponge form by impregnation in combination and dry or wet methods.
As the polymer that can be used, any known polymer generally used in the production of leather-like sheets can be used. For example, polyurethane resins, polyester elastomers, rubber resins Preferable examples include polyvinyl chloride resin, polyacrylic acid resin, polyamino acid resin, silicon resin, and modified products, copolymers, or mixtures thereof.

These polymer polymers are impregnated into the fiber entangled body as an aqueous dispersion or an organic solvent solution, and when using an aqueous dispersion, the dry method is mainly used. When using an organic solvent solution, the wet method is mainly used. Coagulate in a sponge. When using an aqueous dispersion, if a heat-sensitive gelling agent is added, uniform solidification is possible in the thickness direction by combining dry methods or methods such as steaming or far-infrared heating. Moreover, when using an organic solvent, a more uniform space | gap can be obtained by using a coagulation modifier together. A base material having a texture similar to natural leather and various physical properties suitable for a ball material can be obtained by coagulating a fiber entangled body, in particular, a polymer polymer impregnated in a three-dimensional entangled nonwoven fabric into a sponge shape. .

In the present invention, among the polymer polymers impregnated in the fiber entangled body, a polyurethane-based resin is preferably used from the viewpoint of the texture and the balance of various properties in a composite state with the fiber entangled body.
Representative examples of this polyurethane resin include, for example, at least one polymer diol selected from polyester diol having an average molecular weight of 500 to 3000, polyether diol, polyester ether diol, polylactone diol, polycarbonate diol, and the like, Aromatic, alicyclic and aliphatic organics such as tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate At least one organic diisocyanate selected from diisocyanates and the like and active water such as diol, diamine, hydroxyamine, hydrazine, hydrazide Atoms various polyurethane obtained by reacting at least one chain extender selected from low molecular weight compound at a predetermined molar ratio and the like having at least two. If necessary, polyurethane may be a mixture of multiple types of polyurethane, or used as a polymer composition obtained by adding a polymer such as synthetic rubber, polyester elastomer, or polyvinyl chloride. You can also.

In the case of using the above-mentioned ultrafine fiber-generating fiber as the fiber, it is in the stage of the composite sheet after impregnating and solidifying the polymer solution or dispersion, or in the stage of the fiber sheet before being impregnated and solidified. Thus, by converting the ultrafine fiber-generating fiber into an ultrafine fiber bundle by performing ultrafine fiber treatment, a leather-like fiber substrate composed of an ultrafine fiber entangled body and a polymer can be obtained. When ultrafine fiber processing is performed at the composite sheet stage, particularly in the case of sea-island type fibers, the sea component polymer is removed and voids are generated between the ultrafine fiber bundle and the polymer, and the polymer Since the restraint of the ultrafine fiber bundle due to is weakened, the texture of the leather-like substrate tends to be softer, and this method can be preferably employed in the present invention.
On the other hand, when the ultrafine fiber treatment is performed at the fiber sheet stage, the ultrafine fiber bundle is strongly restrained by the polymer, so the texture of the leather-like base material tends to become harder, but the leather-like base It is possible to suppress the tendency to become harder by reducing the polymer ratio in the material, and when the purpose is to achieve a solid texture with a sense of fulfillment obtained when the fiber ratio is higher. It is also a preferred method.

  The thickness of the fiber base material used in the present invention can be arbitrarily selected depending on the intended use, for example, the surface material of the ball, depending on the type of ball, the required physical properties, or the texture preferred by the player. Although not particularly limited, it is preferably 0.4 to 3.0 mm. If the thickness of the fiber base is 0.4 mm or more, not only ball materials but also cover materials for grips such as various rackets, handles, and handrails, tensile strength, tear strength, or abrasion resistance It is possible to secure the minimum required mechanical properties such as properties. On the other hand, if the thickness of the fiber base is 3.0 mm or less, there is no influence on the weight of the product itself using a sheet-like material such as a ball, a racket, or a handle.

  Moreover, the mass ratio of the fiber and the high molecular weight polymer in the fiber substrate may be appropriately selected for adjusting the physical properties and the texture, and is not particularly limited in the essential meaning of the present invention. For example, as a leather-like fiber base material that is generally preferred as a texture of a ball material, when the fiber is made into ultrafine fibers at the above-described composite sheet stage, the mass ratio of fiber / polymer is 35 / 65 to 65/35, preferably in the range of 40/60 to 60/40. On the other hand, when ultrafine fibers are formed at the fiber sheet stage, the mass ratio of fiber / polymer is 65/35 to 95 / 5, preferably in the range of 60/40 to 90/10.

Various methods can be adopted as a method of coating the surface of such a fiber base material with a polymer elastic body. For example, a polymer elastic dispersion, solution or melt is continuously applied to the substrate surface by an amount regulated by a certain clearance set between the substrate surface and a knife, bar, roll, etc. Examples thereof include a method of drying in a film state by a dry method or coagulating and drying in a porous state, a method of coagulating and drying in a porous state by a wet method, and a method of melt surface formation.
When a fiber substrate composed of a fiber entangled body and a polymer elastic body is adopted as the fiber substrate, the solidification of the polymer elastic body impregnated into the substrate and the solidification of the polymer elastic body forming the coating layer are simultaneously performed. By adopting a method that can be completed, drying after solidification can be completed in one time, and in the obtained leather-like sheet, a sense of unity between the fiber base material and the polymer elastic body coating layer (porous surface layer) Is a method preferably employed in the present invention.

  As another method for forming a polymer elastic body coating layer on the surface of a fiber base material, a dispersion or solution of a polymer elastic body is once applied to a transfer release sheet such as a film or a release paper. The polymer elastic body is dried into a film state or solidified into a porous state and dried by the same method as described above, and then adhered to the fiber base material with an adhesive, or the polymer elastic body Examples include a method in which a treatment liquid containing a solvent is used for integration by re-dissolution, and then the release transfer sheet is peeled off. Similarly, after applying a predetermined amount of the dispersion or solution of the polymer elastic body to the transfer release sheet, before drying or coagulating, or pasting the substrate on the way and coagulating the polymer elastic body coating layer It is also possible to adopt a method of integrating the substrate and the substrate.

The polymer elastic body forming the coating layer is preferably a resin that can impart a certain degree of non-slip property rather than a resin that is slippery as the resin itself. For example, synthetic rubber, polyester elastomer, polyvinyl chloride, polyurethane Series resins can be used. Among these, from the viewpoint of balance such as elasticity, softness, wear resistance, and formation of a porous state, a polyurethane-based resin is preferably used in the same manner as the polymer elastic body contained in the fiber entangled body.
Examples of the polyurethane resin include the various types of polyurethane described above. Further, if necessary, a mixture of plural types of polyurethane may be used, and a polymer composition mainly composed of polyurethane obtained by adding a polymer such as synthetic rubber, polyester elastomer and polyvinyl chloride. It can also be used as As the polyurethane used as the main component, a polyurethane-based polymer diol represented by polytetramethylene glycol is preferably used as the main component in terms of hydrolysis resistance and elasticity.
When polyurethane is used as the polymer elastic body, a polyurethane-based solution is applied on the fiber substrate, and then immersed in a treatment bath containing a polyurethane poor solvent to solidify the polyurethane into a porous state. be able to. Typically, water is preferably used as the poor solvent for polyurethane. However, when a good solvent for polyurethane such as dimethylformamide is mixed with water, which is a poor solvent, as a treatment bath, the mixing ratio is appropriately set. Thus, the solidified state, that is, the porous state and shape can be controlled, and this method is preferably employed.

  Additives such as a colorant, a light fastness agent, and a dispersant are added to the solution or dispersion of the polymer elastic body to be applied on the fiber substrate, depending on the purpose. As other additives, in order to control the porous shape, in addition to the foaming agent in the case of dry foaming, a coagulation regulator in the case of wet coagulation is selected as necessary, alone or several It is also preferred to add seeds in combination.

EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In addition, unless otherwise indicated, the part and% in an Example are related with mass.
Further, the wear resistance, cushioning properties and flight properties (controllability) were evaluated by the following methods.
[Abrasion resistance]
The ball was repeatedly applied 20,000 times to a plywood 1.6 m away at a firing speed of 37 km / hour at an incident angle of 60 degrees, and the state of the ball surface thereafter was observed and evaluated as follows.
Practical problem-free level: No peeling of the epidermis, no significant dirt.
Practical problem level: The skin is peeled around the air inlet and on the ball surface. Or it is extremely dirty.
[Cushioning]
Ten volleyball players selected arbitrarily received a reception, and compared with the conventional volleyball (Comparative Example 1), the impact property when hitting the hand was evaluated.
[Toss control]
Ten volleyball players selected arbitrarily were tossed, and compared with the conventional volleyball (Comparative Example 1), whether or not the ball flew to the target position was evaluated.
[Serve control]
Ten volleyball players selected arbitrarily served and evaluated whether or not the ball flew to the target position as compared with the conventional volleyball (Comparative Example 1).
[Smoothness of stall at the time of ball flight]
When the ball is launched at an initial velocity of about 50km / h and a launch angle of 15 degrees, the trajectory of the ball is shot with a high-speed camera, and the trajectory is longer than the conventional ball's stall rate (the trajectory from the top to the top) It is said that the stall at the time of flight is smooth.

Example 1
(1) A sea-island mixed spun fiber, in which the island component is 6-nylon and the sea component is made of high-fluidity low-density polyethylene (sea component / island component ratio = 50/50), was melt-spun. The obtained fiber was drawn, crimped and cut to obtain a staple having 3.5 denier and a cut length of 51 mm. The staple was passed through a card and laminated as a web by a cross wrapper method. Next, a non-woven fabric having a weight per unit area of 450 g / m ² was obtained by needle punching with a needle penetration density of 980 P / cm ² using a felt needle with one barb on the needle. The nonwoven fabric is dried by heating, pressed to smooth the surface, impregnated with a 13% polyester polyurethane dimethylformamide (DMF) solution, coagulated with an aqueous solution of DMF, washed with hot water, and polyethylene in the fiber with hot toluene. Was extracted to obtain an artificial leather-like fiber substrate made of 6-nylon ultrafine fibers and porous polyurethane.

(2) The polyether-based polyurethane onto the surface of artificial leather-like fiber substrate (manufactured by DIC Corporation, MP-145) having a solid content of 20% DMF solution 400 g / m ² was applied in the coagulation in water Thus, a polymer elastic body coating layer that became a porous surface layer was formed. On top of that, using an embossing roll colored with an ether-based polyurethane ink containing a white pigment and having a pyramid-shaped convex part having a height of 0.5 mm and a vertical projection area of 4 mm ² , the temperature is 170 ° C. and the pressure is 10 kg. Embossing was performed at a process speed of 1 m / min. The obtained concave shape has almost the same depth at any place, and the average value is 260 μm. The vertical projection area of the concave portion, that is, from the upper surface direction perpendicular to the sheet surface, The projected areas of the recesses are almost the same size, the average value is 3 mm ² , the average interval between the recesses is 2.0 mm, and the sum of the vertical projected areas of the individual recesses The ratio was 19% with respect to the surface area of the coating layer.
(3) Volleyball covered with the obtained sheet was prepared, and 10 volleyball players were arbitrarily selected to evaluate the ball. As a result, compared to the conventional volleyball (Comparative Example 1), the toss and the serve are both hit at the target position, and the stall speed at the time of flight of the ball is smoother than that of the conventional ball. The ball has aptitude that could not be realized by conventional balls. Also, the wear resistance of the ball is at a level that causes no problem in practical use, and even when it is actually used for about 6 months, no tearing or large scratches are seen due to wear, and good controllability is maintained. In addition, as for cushioning properties, the impact properties felt on the fingertips and arms when receiving were at a level with no problem.

Example 2
(1) In Example 1, using an embossing roll having a truncated pyramidal projection with a height of 0.5 mm and a vertical projection area of 3 mm ² , a temperature of 170 ° C., a pressure of 10 kg / cm, and a processing speed of 1 m / min. The process was carried out under the same conditions as in Example 1 except that the embossing was performed. The obtained concave shape has substantially the same depth at any location, and the average value thereof is 200 μm, and the vertical projection area of the concave portion, that is, from the upper surface direction perpendicular to the sheet surface. The projected area of the recesses is almost the same size for all the recesses, the average value is 2 mm ² , the average interval between the recesses is 2.5 mm, and the ratio of the total projected area of the recesses is covered It was 9% based on the layer surface area.
(2) A volleyball having the obtained sheet on its surface was prepared and evaluated in the same manner as in Example 1. As compared with the conventional volleyball (Comparative Example 1), both the toss and the serve were aimed at. It was evaluated that the ball was in a position and the stalling speed of the ball during flight was smoother than that of the conventional ball. Further, the wear resistance of the ball was at a level that causes no practical problems. In addition, as for the cushioning property, the impact property felt on the fingertip and arm when receiving was at a level where there is no problem.

Example 3
(1) 100% modulus 100 kg / cm ² polyester polyurethane 13% dimethylformamide copolymerized with polyethylene propylene adipate, 4,4'-diphenylmethane-diisocyanate and ethylene glycol on the same non-woven fabric as (1) of Example 1 Immediately after impregnation with the solution, 100% modulus composed of polyhexacarbonate glycol, polymethylenepropylene adipate, methylenediamine and copolymerized with n-hexane diisocyanate, 4,4'-diphenylmethane diisocyanate, ethylene glycol. A 40 kg / cm ² polycarbonate polyurethane 20% dimethylformamide solution was coated and coagulated in a coagulation bath of DMF / water = 30/70 to obtain a porous structure. Subsequently, the polyethylene in the fiber was extracted and removed by washing with hot water and hot toluene to obtain an artificial leather-like fiber base material composed of 6-nylon ultrafine fibers and porous polyurethane.
(2) Colored with an ester-based polyurethane ink containing a yellow pigment, and an embossing roll having a truncated pyramid-shaped projection having a height of 0.5 mm and a vertical projection area of 4 mm ² is used, and the temperature is 170 ° C. The embossing was performed at a pressure of 10 kg / cm and a processing speed of 1 m / min.
The obtained concave shape has substantially the same depth at any place, and the average value is 250 μm. The vertical projected area of the concave portion, that is, from the upper surface direction perpendicular to the sheet surface. The projected areas of the recesses are almost the same size, the average value is 3 mm ² , the average interval between the recesses is 2.0 mm, and the sum of the vertical projected areas of the individual recesses The ratio was 19% with respect to the surface area of the coating layer.
(3) Next, using an embossing roll having a truncated pyramid-shaped projection having a height of 70 mm and a vertical projection area of 0.03 mm ² , a temperature of 150 ° C., a pressure of 6 kg / cm, a processing speed of 2 m / Embossing was performed in minutes to form secondary recesses in portions other than the recesses (upper surface of the protrusions). The secondary concave portion had a depth of 48 μm, and the ratio of the sum of the vertical projected areas of the individual secondary concave portions to the coating layer surface area was 7%.
(4) A volleyball having the obtained sheet on its surface was prepared and evaluated in the same manner as in Example 1. As compared with the conventional volleyball (Comparative Example 1), both of them were aimed at toss and serve. It was evaluated that the ball was in a position and the stalling speed of the ball during flight was smoother than that of the conventional ball. Further, the wear resistance of the ball was at a level that causes no practical problems.
Moreover, when the beach volleyball which has the obtained sheet | seat on the surface was produced and used, it was the same evaluation as the above.

Example 4
(1) In Example 1, using an embossing roll having a truncated pyramidal projection with a height of 0.5 mm and a vertical projection area of 3 mm ² , a temperature of 170 ° C., a pressure of 10 kg / cm, and a processing speed of 1 m / min. The process was carried out under the same conditions as in Example 1 except that the embossing was performed. The obtained concave shape has substantially the same depth at any location, and the average value thereof is 200 μm, and the vertical projection area of the concave portion, that is, from the upper surface direction perpendicular to the sheet surface. The projected area of the recesses is almost the same size for all the recesses, the average value is 2 mm ² , the average interval between the recesses is 2.5 mm, and the ratio of the total projected area of the recesses is covered It was 9% based on the layer surface area.
(2) Next, using an embossing roll having a pyramid-shaped convex part having a height of 55 mm and a vertical projection area of 0.08 mm ² thereon, a temperature of 150 ° C., a pressure of 6 kg / cm, a processing speed of 2 m / Embossing was performed in minutes to form secondary recesses in portions other than the recesses (upper surface of the protrusions). The secondary recesses were 40 μm in depth, and the ratio of the sum of the vertical projection areas of the individual secondary recesses to the coating layer surface area was 8%.
A volleyball having the obtained sheet on the surface was prepared and evaluated in the same manner as in Example 1. As compared with the conventional volleyball (Comparative Example 1), the ball was hit at a target position at the time of toss and serve. In addition, the evaluation was that the stall at the time of flight of the ball was smoother than that of the conventional ball. Further, the wear resistance of the ball was at a level that causes no practical problems.
Moreover, when the beach volleyball which has the obtained sheet | seat on the surface was produced and used, it was the same evaluation as the above.

Example 5
(1) A sheet was obtained in the same manner as in (1) and (2) of Example 1 until the polymer elastic body coating layer was laminated on the surface of the fiber substrate and discontinuous recesses were formed on the surface of the coating layer. .
Next, using an embossing roll having a truncated pyramidal projection with a depth of 60 mm and a vertical projection area of 0.06 mm ² , the embossing was performed at a temperature of 150 ° C., a pressure of 6 kg / cm, and a processing speed of 2 m / min. A secondary concave portion was formed in a portion other than the concave portion (the upper surface of the convex portion). The secondary recesses were 38 μm in depth, and the ratio of the sum of the vertical projection areas of the individual secondary recesses to the surface area of the coating layer was 12%.
(2) A volleyball covered with the sheet obtained as described above was prepared and evaluated in the same manner as in Example 1. As compared with the conventional volleyball (Comparative Example 1), it was more aimed at toss and serve. The ball has the aptitude that could not be realized by the conventional balls, in which the ball was hit at a different position and the stall speed during flight of the ball was smoother than that of the conventional ball. Also, the wear resistance of the ball is at a level that causes no problem in practical use, and even when it is actually used for about 6 months, no tearing or large scratches are seen due to wear, and good controllability is maintained.
Moreover, when the beach volleyball which has the obtained sheet | seat on the surface was produced and used, it was the same evaluation as the above.

Comparative Example 1
In Example 1, the shape used for a general volleyball as a concave shape imparted by an embossing roll, that is, there are many pore-shaped patterns having a depth of about several μm, and the shape is substantially flat. It processed on the conditions similar to Example 1 except having used the embossing roll from which a sheet | seat surface is obtained. When the volleyball having the obtained sheet on its surface was prepared and used, the wear resistance of the ball was at a level that was practically no problem as in Example 1, and the controllability when tossing was also used conventionally. It was not much different from the ball and the degree of stall at the time of flight was the same as that of the conventional ball, but the toss slipped when wet with sweat, as I was concerned about with the conventional ball Because it was easy, it was evaluated that it was very difficult to control.
Moreover, when the beach volleyball which has the obtained sheet | seat on the surface was produced and used, it was the same evaluation as the above.

Comparative Example 2
In Example 1, using an embossing roll having a hemispherical convex part with a height of 1.0 mm and a vertical projection area of 8 mm ² , the embossing roll was performed at a temperature of 170 ° C., a pressure of 10 kg / cm, and a processing speed of 1 m / min. The process was performed under the same conditions as in Example 1 except that the test was performed. The obtained concave shape has almost the same discontinuous depth at any location, the average value is 400 μm, and the vertical projection area of the concave portion is almost the same in any concave portion. The average value is 4.9 mm ² , the average distance between the recesses is 1.3 mm, and the ratio of the total vertical projection area of the recesses is 34% with respect to the surface area of the coating layer. It was. When the volleyball having the obtained sheet on its surface was prepared and used, the wear resistance of the ball was almost the same as in Example 1 and was at a level that was not a problem for practical use. Therefore, it was an evaluation that it was hard to toss rather than good controllability.

Comparative Example 3
In Example 1, using an embossing roll having a hemispherical projection having a height of 0.8 mm and a vertical projection area of 8 mm ² , the embossing roll was performed at a temperature of 170 ° C., a pressure of 10 kg / cm, and a processing speed of 1 m / min. The process was performed under the same conditions as in Example 1 except that the test was performed. The obtained concave shape has almost the same discontinuous depth at any location, the average value is 400 μm, and the vertical projection area of the concave portion is almost the same in any concave portion. The average value is 6.2 mm ² , the average distance between the recesses is 2.6 mm, and the ratio of the sum of the vertical projected areas of the recesses is 21% with respect to the surface area of the coating layer. It was. When the volleyball having the obtained sheet on its surface was prepared and used, the wear resistance of the ball was almost the same as in Example 1 and was at a level that was not a problem for practical use. Therefore, it was an evaluation that it was hard to toss rather than good controllability.

Comparative Example 4
In Example 1, using an embossing roll having a hemispherical projection having a height of 0.8 mm and a vertical projection area of 3 mm ² , the embossing roll was performed at a temperature of 170 ° C., a pressure of 10 kg / cm, and a processing speed of 1 m / min. The process was performed under the same conditions as in Example 1 except that the test was performed. The obtained concave shape has almost the same discontinuous depth at any location, the average value is 400 μm, and the vertical projection area of the concave portion is almost the same in any concave portion. The average value is 1.8 mm ² , the average distance between the recesses is 7.4 mm, and the ratio of the total vertical projection area of the recesses is 2% with respect to the surface area of the coating layer. It was. When a volleyball having the obtained sheet on the surface was prepared and used, the wear resistance of the ball was almost the same as that of Example 1 and was at a level that was not a problem in practice, but I am concerned about the conventional ball. As described above, it was evaluated that it was very difficult to control because the toss was slippery when wet with sweat.

  Since the ball of the present invention has a large number of discontinuous recesses, the controllability of the ball can be improved by suitably controlling the contact state between the fingertip and the ball surface during tossing. Due to the next unevenness, it also has an excellent non-slip property that is difficult to slip even when wet with sweat or water. In addition, not only is it excellent in controllability as a play total, it also has the effect of suppressing the blurring of the trajectory during flight such as serve and feeling the degree of stall during flight smoothly, It is also excellent, and can be used very suitably as a ball hit directly with a hand such as volleyball or beach volleyball.

It is a cross-sectional schematic diagram which shows an example (a linear part is a convex part) of the uneven | corrugated | grooved part of the sheet-like material used for the ball | bowl of this invention. It is a cross-sectional schematic diagram which shows an example (a linear part is a convex part of a secondary uneven part) of the secondary uneven part of the sheet-like material used for the ball | bowl of this invention. It is a cross-sectional schematic diagram explaining the depth (distance: D) of the recessed part of the uneven | corrugated | grooved part of the sheet-like material used for the ball | bowl of this invention. It is a cross-sectional schematic diagram explaining the boundary (B) of the recessed part and flat part of a semicircular cross section in the sheet-like material used for the ball | bowl of this invention. It is a cross-sectional schematic diagram explaining the boundary (B) of the recessed part and flat part of a trapezoidal cross section in the sheet-like material used for the ball | bowl of this invention. It is a plane schematic diagram which shows an example (the filling part is a recessed part of a secondary uneven part) of the secondary uneven part of the sheet-like material of this invention.

Explanation of symbols

1: Covering layer 2: Fiber substrate 3: Concave part 4: Convex part 5: Secondary concavity 6: Secondary convex part D: Depth (distance) of concavity
B: Boundary between the concave portion and the flat portion X: Vertical projection plane of the concave portion

Claims (12)

A polymer elastic body coating layer is laminated on the surface of the fiber substrate, and continuous convex portions and discontinuous concave portions are formed on the surface of the coating layer, and the discontinuous concave portions are formed with an average interval of 0.5 to 3 mm. The concave portion has a depth of 50 to 500 μm, the vertical projected area of each concave portion is 1 to 5 mm ² , and the ratio of the total vertical projected area of each concave portion to the coating layer surface area is 3 to 30%. A ball for volleyball or beach volleyball made of a characteristic sheet.   2. The ball for volleyball or beach volleyball according to claim 1, wherein a secondary unevenness having a secondary recess having a depth less than the depth of the recess and 10 to 100 μm is formed on the surface of the coating layer. .   The ball for volleyball or beach volleyball according to claim 2, wherein the secondary unevenness is formed in a portion other than the recess on the surface of the coating layer.   The ball for volleyball or beach volleyball according to claim 2 or 3, wherein the secondary irregularities are formed on an upper surface of a convex portion on the surface of the coating layer. The secondary recess is discontinuous, the vertical projection area is 0.01 to ¹ mm ² , and the ratio of the sum of the vertical projection areas of the individual secondary recesses to the coating layer surface area is 1 to 30%. 4. A ball for volleyball or beach volleyball as described in any one of 4 above.   The ball according to any one of claims 1 to 5, wherein the fiber base material is a leather-like fiber base material comprising a fiber entangled body and a polymer.   The ball according to any one of claims 1 to 6, wherein the fiber base material is obtained by impregnating a polymer in the interior of a three-dimensional entangled nonwoven fabric.   The ball according to claim 6, wherein the polymer is a polyurethane resin.   The ball according to any one of claims 1 to 8, wherein the fiber substrate has a thickness of 0.4 to 3.0 mm.   The ball according to claim 1, wherein the polymer elastic body is a polyurethane-based resin.   The ball according to any one of claims 1 to 10, wherein the polymer elastic body coating layer has a thickness of 0.1 to 0.3 mm.   The ball according to any one of claims 1 to 11, wherein a cross-sectional shape in the thickness direction of the concave portion is an arc shape, a semicircular shape, or a trapezoidal shape.

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